EP2546176B1

Movatterモバイル変換

Info

Publication number: EP2546176B1
Application number: EP12183371.9A
Authority: EP
Inventors: Fiorenzo Parrinello; Zeno Zuffa; Matteo Camerami; Ivan Bonzi; Gabriele Stocchi
Original assignee: Sacmi Imola SC
Current assignee: Sacmi Imola SC
Priority date: 2008-04-18
Filing date: 2009-04-16
Publication date: 2016-01-20
Anticipated expiration: 2029-04-16
Also published as: EP2786949A3; JP2011520643A; US20140027956A1; WO2009127962A3; EP2282956A2; BRPI0910713A2; EP2786949A2; US9446550B2; US20110109018A1; US8556620B2; MX2010011484A; JP2014128981A; US9028739B2; EP2786949B1; US20140338291A1; CN102744800B; EP2546176A2; KR20100135897A; CN102046498A; EP2546176A3

Description

The invention relates to a method and apparatus for forming plastics for producing preforms that are subsequently expanded to obtain containers according toclaims 1, 13.
Moulding machines are known that are arranged for forming plastics to obtain preforms. Such machines can be compression-moulding machines, or injection-moulding machines.
Blowing machines are further known that are supplied with preforms and blow the preforms to obtain containers.
Filling machines are also known that fill containers with a product.
An apparatus is further known comprising a moulding machine for compression-moulding plastics to obtain preforms, a thermal conditioning station for the preforms, arranged downstream of the moulding machine, and a blowing machine arranged downstream of the thermal conditioning station and suitable for blowing the preforms so as to obtain containers therefrom.
The preforms are first compression-moulded, and subsequently removed from the moulding machine to be transferred to the thermal conditioning station, where they are heated to a temperature that is suitable for the blow-moulding step. During the advancing from the moulding machine to the thermal conditioning station, the preforms are arranged sequentially one after the other and move along a preset advance path.
The preforms, after being compression-moulded and before they advance to the thermal conditioning station, require a cooling step that is suitable for stabilising the shape thereof and for avoiding crystallisation phenomena that compromise the transparency of a bottle that is subsequently obtained from the preform and alter the mechanical features thereof.
The duration of the cooling step depends on the type and/or on the geometry of the preforms. Thus, a given period of time required for the cooling step corresponds to a given geometry and/or type of preform. For given types or geometries of preforms it is necessary to slow the moulding machine so as to support the preforms for longer, thus enabling suitable cooling. This entails an undesired reduction in productivity in all those cases in which it is not possible to modify cooling efficacy.
The preforms, before being positioned on the blowing machine, have to be suitably heated, and for this purpose remain in the thermal conditioning station for a further set period of time that is a function of the geometry and/or of the type of preforms thereof. DocumentEP-A-1679178 discloses preamble of apparatus claim 1 and ofmethod claim 13.
A drawback of the aforesaid apparatus is that it has productivity that is limited by the time required for the preforms to be thermally conditioned. In particular, the productivity depends on the period of time that the preforms, arranged in sequence one after another along the advance path, require for the cooling step that is subsequent to compression-moulding.
In other words, the operation of the moulding machine located upstream and of the blowing machine located downstream depends on, and is constrained by, the period of time required for cooling the preforms that have just been moulded, this period of time depending on the type/geometry of the preform.
An object of the invention is to obtain an apparatus provided with a machine for producing preforms and with a machine for blowing such preforms to obtain containers that are operationally connected together in a flexible manner.
A further object of the invention is to obtain a method that enables a product to be packaged inside a container in a hygienic manner.
Another object is to obtain an apparatus for producing containers and for packaging a product in such containers immediately after such containers have been produced, in which the containers have not been damaged between the producing step and the filling step.
Another object is to obtain an apparatus for producing containers and for packaging a product in such containers that is provided with great efficiency.
A still further object is to obtain an apparatus for producing containers and for filling such containers with a product that is very compact.
An apparatus is provided comprising a first operating machine arranged for processing objects, a second operating machine positioned downstream of said first operating machine and arranged for further processing said objects, accumulating means interposed between said first operating machine and said second operating machine and arranged for receiving said objects and control means arranged for detecting a parameter indicating the quantity of said objects contained in said accumulating means and regulating the operation of said second operating machine on the basis of said parameter.
In one embodiment, the first operating machine is a compression-moulding machine arranged for forming plastics to obtain preforms and the second operating machine is a blow-moulding machine arranged for blowing the preforms to obtain containers.
Owing to this aspect, it is possible to obtain a very flexible apparatus. The compression-moulding machine and the blow-moulding machine have distinct driving devices. The speed of the blow-moulding machine is, within a certain limit, independent of the speed of the compression-moulding machine and can be varied according to the number of preforms contained inside the accumulating means. Further, stopping the compression-moulding machine does not necessary entail stopping the blow-moulding machine, and vice versa.
Furthermore an apparatus is provided comprising a compression-moulding machine, suitable for compression-moulding plastics to obtain preforms, a blow-moulding machine, suitable for blowing said preforms to obtain containers, a thermal conditioning station for said preforms, interposed between said compression-moulding machine and said blow-moulding machine, moving means for moving said preforms to an intermediate zone between said compression-moulding machine and said thermal conditioning station, characterised in that said moving means is configured so as to advance said preforms along advance paths of variable length to vary the dwelling time of said preforms in said intermediate zone.
There is also provided a method comprising compression-moulding plastics to obtain preforms in a first operating zone, blow-moulding said preforms to obtain containers in a second operating zone, thermally conditioning said preforms in a third operating zone interposed between said first zone and said second zone, moving said preforms to an intermediate zone interposed between said first operating zone to said second operating zone, whereby said moving comprises advancing said preforms along advance paths of variable length to vary the dwelling time of said preforms in said intermediate zone.
Owing to these aspects, it is possible to produce containers with high levels of efficiency and productivity.
Furthermore a method is provided, comprising dispensing plastics in pasty state, during said dispensing said plastics having a dispensing temperature, compression-moulding said plastics to obtain a preform, blowing said preform to obtain a container, during said blowing said plastics having a blowing temperature, filling said container with a product, during said filling said plastics having a filling temperature, in which said dispensing temperature is greater than said blowing temperature and said blowing temperature is greater than said filling temperature.
Owing to this aspect, it is possible to package a product in a hygienically controlled manner. The dispensing temperature (i.e. the temperature of the plastics exiting a plasticising device, for example an extruder), is in fact greater than the temperature at which the destruction of possible microorganisms, in particular viruses and/or bacteria, is assured.
As a preform is obtained from the plastics at high temperature that is expanded within a short space of time to obtain a container that, in turn, is filled within a short space of time, all possibility of pollution is substantially eliminated.
In addition, the filling temperature is less than the blowing temperature by an amount that is such as to enable the shape of the container to be stabilised and not to be deformed during filling, in particular owing to the interaction with the product that has to be packaged.
The product, in particular if it comprises a fluid material, can contribute to cooling the plastics. This enables the container-manufacturing cycle to be shortened and simplified.
In one embodiment, after the compression-moulding step and before the blow-moulding step, the preform is cooled to a thermal treatment temperature that is less than the blowing temperature and the preform is subsequently heated to the blowing temperature.
After the plastics have been subjected to compression-moulding, the plastics have a higher temperature at an internal zone of the walls that bound the body of the preform and a lower temperature at external zones of the walls that bound the body of the preform. This is because the external zones of the walls that bound the body of the preform have interacted with a forming mould in which cooling means are provided, for example, with conduits through which a cooling fluid circulates. In addition, the external zones of the walls that bound the body of the preform, after extraction of the preform from the forming mould, have been cooled by the air in the environment. The heating of the preforms from the thermal treatment temperature to the blowing temperature is obtained by giving heat to the preforms by means of heating means positioned outside the latter. Consequently, the external zones of the walls that bound the body of the preform receive a quantity of heat that is greater than the quantity of heat received from the internal zone of the walls that bound the body of the preform. In this manner, the difference in temperature between the internal zones of the walls that bound the body of the preform and the external zone of the walls that bound the body of the preform is noticeably reduced, or is even substantially eliminated. This enables the subsequent step of blowing the preform to be improved, which is optimal if the temperature of the walls that bound the body of the preform is substantially uniform along the thickness of the walls thereof.
Furthermore an apparatus is provided, comprising a compression-moulding machine arranged for compression-moulding plastics to obtain preforms, a blow-moulding machine arranged for blowing said preforms to obtain containers, moving means arranged for removing said preforms from said compression-moulding machine and delivering said preforms to said blow-moulding machine, a filling machine arranged for filling said containers with a product and transferring means arranged for transferring said containers from said blow-moulding machine to said filling machine, maintaining said containers spaced apart from one another.
Owing to this aspect, it is possible to obtain an apparatus in which the containers are not damaged during transfer from the blow-moulding machine to the filling machine. The containers, which owing to the high temperature of some parts thereof are rather delicate, could be deformed and/or damaged so as to have aesthetic defects if they were placed in mutual contact immediately after being removed from the blow-moulding machine. This does not occur in this apparatus as the transferring means prevents the containers from interacting with one another.
In an embodiment, the transferring means maintains the containers at a set distance from one another. In other words, the transferring means removes the containers from the blow-moulding machine according to a preset removal step and delivers the containers to the filling machine according to a preset delivery step (the removal step and the delivery step being able to be the same as or different from one another).
The blow-moulding machine and the filling machine can thus operate synchronously, which enables a very efficient apparatus to be obtained.
Furthermore apparatus is provided comprising a moulding machine provided with a movable supporting device that supports mould means comprising compression-moulding means arranged for compression-moulding plastics to obtain preforms and blow-moulding means arranged for blowing said preforms to obtain containers, said apparatus further comprising a filling machine arranged for filling said containers with a product and moving means arranged for removing said containers from said moulding machine and delivering said containers to said filling machine.
Owing to this, it is possible to obtain a very compact apparatus for packaging a product. In fact, the preforms are formed and blown on the same moulding machine and the containers obtained by blowing the preforms are immediately filled in a filling machine positioned downstream of the moulding machine.
In an embodiment, the compression-moulding means comprises compression-moulding die means cooperating with punch means for compression-moulding the plastics and the blow-moulding means comprises blow-moulding die means cooperating with the aforesaid punch means to blow the preforms to obtain the containers. In other words, the compression-moulding die means and the blow-moulding die means interact with the punch means the one after another. Initially, the compression-moulding die means and the punch means interact to form a preform. Subsequently, the compression-moulding die means moves away from the punch means and the preform is maintained on the punch means. Still subsequently, the blowing die means moves towards the punch means and interacts with the punch means to define a forming chamber inside which the preform is expanded.
In one embodiment, the mould means comprises a plurality of moulds supported by the movable supporting device.
The invention can be better understood and implemented with reference to the attached drawings in which:

Figure 1 is a schematic layout of an apparatus for forming preforms made of plastics, expanding the preforms to obtain containers and filling the containers with a product;Figure 2 is a detail ofFigure 1;
Figure 3 is a graph that shows how the temperature of the plastics varies over time during the plastics dispensing step, during the preform compression-moulding step, during the preform expansion step to obtain a container and during the container-filling step;
Figure 4 is a graph like that inFigure 3 that further shows how the temperature of the plastics varies over time during a thermal conditioning step of the preform, interposed between the preform forming step and the preform expansion step;
Figure 5 is a schematic layout of a further embodiment of an apparatus for forming preforms made of plastics, expanding the preforms to obtain containers and filling the containers with a product;
Figure 6 is a perspective view of a mould of the apparatus inFigure 5 arranged for compression-moulding a dose of plastics to obtain a preform and for expanding the preform to obtain a container;
Figures 7 to 10 are sections taken along a longitudinal plane of the mould inFigure 6 that show subsequent steps of a work cycle of the mould;
Figure 11 is a perspective view that shows a moving carousel and a step-varying carousel of the apparatus inFigure 5;
Figures 12 to 17 are plan views that show the moving carousel and the step-varying carousel inFigure 11 in subsequent steps of an operating cycle;
Figure 18 is a schematic and fragmentary layout of a still further embodiment of an apparatus for forming preforms made of plastics, expanding the preforms to obtain containers and filling the containers with a product;
Figure 19 is a detail ofFigure 18;
Figure 20 is a schematic layout of a version of the apparatus shown inFigure 18;
Figure 21 is a detail ofFigure 20;
Figure 22 is a detail ofFigure 21;
Figure 23 is a schematic layout of another embodiment of an apparatus for producing containers;
Figure 24 shows a detail inFigure 23 in a first operating configuration;
Figure 25 shows the same detail inFigure 24 in a second operating configuration;
Figure 26 shows the same detail inFigure 24 in a third operating configuration;
Figure 27 is a schematic layout of a further embodiment of the apparatus for producing containers;
Figure 28 is a schematic layout of a still further embodiment of the apparatus for producing containers.

With reference toFigures 1 and2, there is shown an apparatus 1 comprising a plasticising device, for example an extruder 2, arranged for dispensing plastics in a pasty state. With the extruder 2 a cutting means is associated, which is not shown, that divides the plastics into doses.
The apparatus 1 further comprises a compression-moulding carousel 3 provided with a plurality of compression-moulding moulds 4 -for example positioned at constant angular intervals on a peripheral zone of the compression-moulding carousel 3 - that compression-mould the doses to obtain preforms. Each compression-moulding mould 4 comprises a female half mould and a male half mould that are movable towards and away from one another, the female half mould being provided with a cavity arranged for receiving a dose and the male half mould being provided with a punch arranged for penetrating inside the cavity to shape the dose.
The apparatus 1 further comprises a movingcarousel 5 interposed between the extruder 2 and the compression-moulding carousel 3. The movingcarousel 5 removes the doses from the extruder 2 and inserts the doses into the compression-moulding moulds 4. The movingcarousel 5 further removes the preforms from the compression-moulding moulds 4 and delivers the preforms to afirst transfer carousel 6.
The apparatus 1 further comprises a blow-moulding carousel 7 provided with a plurality of blow-moulding moulds 16 - for example positioned at constant angular intervals on a peripheral zone of the blow-moulding carousel 7 - that expand the preforms to obtain containers.
Between the compression-moulding carousel 3 and the blow-moulding carousel 7 athermal conditioning device 17 can be interposed arranged for thermally conditioning the preforms to prepare the preforms for blowing.
Thethermal conditioning device 17 may comprise athermal conditioning carousel 8 and/or one or more thermal conditioning tunnels.
The preforms are introduced into thethermal conditioning device 17 by thefirst transfer carousel 6 and are removed from the thermal conditioning device by asecond transfer carousel 9.
The apparatus 1 further comprises a fillingcarousel 10 on which filling means is provided that fills the containers with a product, this product being able to comprise a liquid material, a powder or granule material, a paste material and the like. The aforesaid product can be, for example, a food product or a cosmetic product.
The apparatus 1 further comprises a transferringdevice 11 that removes the containers from the blow-moulding carousel 7 and delivers the containers to the fillingcarousel 10. The transferringdevice 11 comprises a rotating body 70 that supports a plurality of handlingelements 71, each of which is arranged for removing, retaining and delivering a container.
Each handlingelement 71 comprises agripping element 74, for example shaped as a gripper and arranged for grasping a neck zone of the container.
Each handlingelement 71 comprises afirst arm 72 rotatably supported by the rotating body 70 and asecond arm 73 rotatably supported by thefirst arm 72, the grippingelement 74 being connected to thesecond arm 73.
The transferringdevice 11 comprises first driving means, arranged for moving thefirst arm 72 with respect to the rotating body 70 and second driving means arranged for moving thesecond arm 73 with respect to thefirst arm 72.
In one embodiment, the first driving means comprises a first revolving element rotatably connected to thefirst arm 72 and engaging with a first cam arranged in a fixed position with respect to the rotating body 70 and the second driving means comprises a second revolving element rotatably connected to thesecond arm 73 and engaging with a second cam arranged in a fixed position with respect to the rotating body 70.
Thehandling elements 71 maintain the containers spaced apart from one another. This enables damage to the containers to be avoided even if they are removed from the blow-moulding carousel when the plastics from which they are formed are still at a high temperature, and consequently, the containers are easily deformable.
Thehandling elements 71 are conformed in such a manner as to maintain the containers at a set distance from one another.
Thehandling elements 71 thus remove the containers from the blow-moulding carousel 7 according to a preset removal step and deliver the containers to the fillingcarousel 10 according to a preset delivery step (the removal step and the delivery step being able to be the same as or different from one another).
The blow-moulding carousel 7 and the fillingcarousel 10, can thus function in a synchronous manner, which enables the efficiency of the apparatus 1 to be optimised.
In one embodiment, rather than a single transferring device 11 a plurality of transferring devices arranged one after the other can be provided.
The blow-moulding carousel 7 is provided in a dry zone of the apparatus 1, whilst the fillingcarousel 10 zone is provided in a wet zone of the apparatus 1. Inside the wet zone sanitising treatments take place.
The transferringdevice 11, or the plurality of transferring devices, enable the aforesaid dry zone to be separated and spaced apart from the aforesaid wet zone. The aforesaid wet zone is maintained in slight overpressure - for example with sanitised air - with respect to the aforesaid dry zone.
The transferringdevice 11, or the plurality of transferring devices, by retaining the containers on board for a certain period of time, ensure that the containers are suitably cooled before filling. For this purpose, the transferringdevice 11, or the plurality of transferring devices, may comprise nozzles that direct jets of cooling fluid to the containers, in particular to a bottom zone of the containers, whilst the containers are supported and moved by thehandling elements 71. The apparatus 1 further comprises a cappingcarousel 12 provided with capping means arranged for applying caps to the containers filled with the product. The apparatus 1 further comprises alabelling carousel 13 provided with applicating means arranged for applying labels to the containers filled with the product.
The apparatus 1 is further provided with athird transfer carousel 14 arranged for removing the containers from the fillingcarousel 10 and delivering the containers to the cappingcarousel 12.
The apparatus 1 is further provided with afourth transfer carousel 15 arranged for removing the containers from the cappingcarousel 12 and delivering the containers to thelabelling carousel 13.
According to one operating mode, the preforms, rather than being blown immediately after compression-moulding, can be removed from the apparatus 1 - for example at the second transfer carousel 9 - by a bypass device. In this case, the preforms, in the thermal conditioning device, are subjected to cooling that stabilises the shape thereof. After cooling, the preforms can be stored inside a container and moved without suffering damage or deformation.
The blow-moulding carousel 7 can be supplied, instead of with preforms coming directly from the compression-moulding carousel 3, with cold preforms, for example made previously by the compression-moulding carousel 3 - and subsequently cooled - or manufactured by a different forming device. In this case, the preforms can be introduced inside thethermal conditioning device 17, which heats the preforms in such a manner as to prepare the preforms for subsequent blowing. This operating mode can be applied for particular types of containers - and thus of preforms - that have to be produced in a limited number of examples.
Similarly, according to a further operating mode, the containers, rather than being filled immediately after blowing, can be removed from the apparatus 1 - for example at the transferring device 11 - by a further bypass device. The fillingcarousel 10 can be supplied, rather than with containers coming directly from the blow-moulding carousel 7, with containers manufactured previously.
As shown inFigure 3, the dispensing temperature T1, i.e. the temperature of the plastics when they are dispensed by the plasticising device, is greater than the blowing temperature T2, i.e. than the temperature of the plastics when the preforms are expanded to obtain the containers. The blowing temperature T2 is in turn greater than the filling temperature T3, i.e. than the temperature of the plastics when the containers are filled with the product.
This enables the product to be packaged in the containers in an absolutely hygienic manner. The dispensing temperature T1 is in fact sufficiently high to ensure the elimination of the microorganisms. As the plastics extruded at high temperature are immediately compression-moulded to obtain the preforms, the preforms are immediately expanded to obtain the containers and the containers are immediately filled, the preforms are not contaminated before blowing and the containers are not contaminated before filling.
If the product is colder than the container intended to receive the product, the product contributes to cooling the plastics to the filling temperature T3. This enables the manufacturing cycle of the container to be decreased and the cooling modes to be simplified.
As shown inFigure 4, the preforms can be cooled to a thermal treatment temperature T4 that is less than the blowing temperature T2 and be subsequently heated to the blowing temperature T2.
The preforms, after being extracted from the compression-moulding moulds 4, are provided with walls that bound the body of the preform provided with an internal zone having a greater temperature and with external zones having a lesser temperature.
Cooling the preforms to the thermal treatment temperature T4 and subsequent heating to the blowing temperature T2 enables the difference between the temperature of the aforesaid internal zone and the temperature of the aforesaid external zones to be reduced and possibly to be substantially eliminated. This effect is obtained because the preforms, after being cooled to the thermal treatment temperature T4, are heated with heating means that acts by giving heat to the aforesaid external zones until the temperature of such external zones differs by little from, or substantially equals, the temperature of the aforesaid internal zone.
A substantially uniform temperature profile through the thickness of the walls that bound the body of the preforms constitutes a condition that enables the blowing or stretch-blowing of the preforms to be optimised.
Heating from the thermal treatment temperature T4 to the blowing temperature T2 occurs in a controlled manner, in particular enabling the heat to spread through the thickness of the preforms to prevent the aforesaid heat causing overheating of the external surface of the preforms with respect to the immediately underlying layer.
Cooling the preforms to the thermal treatment temperature T4 and subsequent heating to the blowing temperature T2 is conducted in thethermal conditioning device 17. Thethermal conditioning device 17 is provided with heating elements, for example with infrared heating elements. The heating elements can perform differentiated heating of the preforms, i.e. heat different zones of the preforms in a differentiated manner. In one operating mode, zones of the preforms having a greater thickness are heated more than zones of the preforms having a lesser thickness. In a further operating mode, zones of the preforms intended for being more deformed during expansion are heated more than zones intended for being less deformed during expansion.
The dispensing temperature T1 can be greater than the blowing temperature T2 by an amount comprised between 50 and 195 °C and preferably by an amount comprised between 65 and 175 °C.
The blowing temperature T2 can be greater than the filling temperature T3 by an amount comprised between 30 and 130 °C and preferably by an amount comprised between 70 and 120 °C. The thermal treatment temperature T4 can be less than blowing temperature T2 by an amount comprised between 5 and 85 °C and preferably between 20 and 50 °C.
It has been ascertained experimentally that the temperature differences indicated above enable good results to be obtained.
Experiments conducted have enabled optimal temperature ranges to be achieved.
The dispensing temperature T1 can be comprised in the range between 190-295 °C.
For polyethyleneterephthalate (PET) the dispensing temperature T1 is preferably comprised in the range between 250-285 °C and more preferably in the range between 265-275 °C.
For polypropylene (PP) the dispensing temperature T1 is preferably comprised in the range between 190-230 °C and more preferably in the range between 200-210 °C.
The blowing temperature T2 can be comprised in the range between 90-140 °C.
For polyethyleneterephthalate (PET) the blowing temperature T2 is preferably comprised in the range between 90-115 °C and more preferably in the range between 100-105 °C.
For polypropylene (PP) the blowing temperature T2 is preferably comprised in the range between 125-140 °C and more preferably in the range between 130-135 °C.
The filling temperature T3 can be comprised in the range between 10-60 °C and preferably in the range between 15-30 °C.
For polyethyleneterephthalate (PET) the thermal treatment temperature T4 is preferably comprised in the range between 50-85 °C and more preferably in the range between 65-80 °C. For polypropylene (PP) the thermal treatment temperature T4 is preferably comprised in the range between 55-120 °C and more preferably in the range between 85-110 °C.
With reference toFigures 5 to 10 there is shown anapparatus 101 comprising a plasticising device, for example anextruder 102, arranged for dispensing plastics in a pasty state. Cutting means is associated with theextruder 102, which is not shown, that divides the plastics into doses D. Theapparatus 101 further comprises a formingcarousel 120 provided with a plurality of forming moulds 121 - for example positioned at constant angular intervals on a peripheral zone of the forming carousel 120 - arranged for compression-moulding the doses D to obtain preforms P and for expanding the preforms P to obtain containers C.
Each formingmould 121 comprises apunch 122 that cooperates alternatively with a compression-moulding die 123 for compression-moulding a dose D to obtain a preform P and with a blow-moulding die 124 for expanding the preform P to obtain a container C.
The formingmould 121 further comprises neck-formingmeans 125 arranged for compression-moulding a neck portion of the preform P that is not subsequently deformed when the preform P is expanded.
The compression-moulding die 123 comprises acavity 126 arranged for receiving the dose D. The compression-moulding die 123 is movable along a longitudinal axis of the formingmould 121.
The blow-moulding die 124 comprises afirst half mould 127 and asecond half mould 128 that are movable towards and away from one another transversely to the longitudinal axis of the formingmould 121.
Figure 7 shows a step of an operating cycle of the formingmould 121 in which the compression-moulding die 123 is in a lowered position A, in which it does not interact with thepunch 122, the blow-moulding die 124 is in an open configuration X, in which thefirst half mould 126 and thesecond half mould 127 are spaced away from one another, and a dose D has been introduced inside thecavity 126.
Figure 8 shows a subsequent step of the operating cycle of the formingmould 121 in which the compression-moulding die 123 is in a raised position B in which it cooperates with thepunch 122 and with the neck-formingmeans 125 to compression-mould the dose D to obtain the preform P. The blow-moulding die 124 is maintained in the open configuration X to enable the compression-moulding die 123 to move along the longitudinal axis of the formingmould 121 to move from the lowered position A to the raised position B.
Figure 9 shows a subsequent step of the operating cycle of the formingmould 121 in which the compression-moulding die 123 has moved from the raised position B to the lowered position A. The preform P is retained by the neck-formingmeans 125. Thepunch 122 is maintained inside the preform P.
Figure 10 shows a subsequent step of the operating cycle of the formingmould 121 in which the blow-moulding die 124 is in a closed configuration Y in which thefirst half mould 127 and thesecond half mould 128 define a formingchamber 129 having the shape of the container C that has to be obtained.
A formingelement 130 of thepunch 122 penetrates inside the formingchamber 129 to stretch the preform P. Simultaneously, the preform P is blown by a forming fluid - for example air - dispensed through conduits obtained in thepunch 122, in particular in the formingelement 130. Alternatively, the preform P can be expanded only through the action of the forming fluid, i.e. without the stretching action exerted by the formingelement 130.
In subsequent steps of the operating cycle of the formingmould 121, the blow-moulding die 124 moves from the closed configuration Y to the open configuration X and the neck-formingmeans 125 releases the container C. In this manner, the container C can be removed from the formingmould 121 and the formingmould 121 can start a new operating cycle. The apparatus 1 further comprises a movingcarousel 131 interposed between the extruder 2 and the formingcarousel 120. The movingcarousel 131 removes the doses D from theextruder 102 and inserts the doses D into the forming moulds 121. The movingcarousel 131 further removes the containers C from the forming moulds 121. On the movingcarousel 131, the containers are positioned according to an angular step that has rather a wide extent. This is due to the fact that the formingmoulds 121, owing to the significant overall dimensions thereof, have to be spaced apart by rather wide angles on the formingcarousel 120.
In order to optimise the operation of the devices of the apparatus positioned downstream of the formingcarousel 120 it is appropriate to modify, and in particular reduce the distance between the containers C. This enables, for example, more efficient exploitation of the spaces in the aforesaid devices, inasmuch, with the same dimensions of the devices, the number of containers C increases that can be processed simultaneously by the same device.
For this purpose, the apparatus 1 is provided with a step-varyingcarousel 132 that removes the containers C from the movingcarousel 131 according to a removal step and delivers the containers C to a conveyingdevice 133 according to a delivery step that is less than the removal step.
The conveyingdevice 133 may comprise aconveyor belt 134 that supports a plurality of retainingelements 135, for example conformed as grippers. InFigure 5 and inFigures 11 to 17 only some of the retainingelements 135 supported by theconveyor belt 134 are shown. Each retainingelement 135 is separated from the retainingelements 135 adjacent thereto by a distance corresponding to the delivery step. The step-varyingcarousel 132 comprises a rotating driving device, for example a brushless motor, and a command and control unit that enables the rotation speed of the step-varyingcarousel 132 to be varied.
As shown inFigure 11, the movingcarousel 131 comprises arotating body 136 from which handlingelements 137 project that are intended to remove, retain and deliver the containers C. In the embodiment shown three handlingelements 137 are present positioned at angular intervals of 120° with respect to therotating body 136. The handlingelements 137 are provided with sucking means that enable thehandling elements 137 to retain the containers C by depression. Alternatively, other types of retaining means can be provided, for example mechanical retaining means.
The step-varyingcarousel 132 comprises a rotatingmember 138 from whichgripping elements 139 project that are intended to remove, retain and deliver the containers C. In the embodiment shown there are threegripping elements 139 positioned at angular intervals of 120° with respect to the rotatingmember 138. Thegripping elements 139 are provided with sucking means that enable thegripping elements 139 to retain the containers C by depression. Alternatively, retaining means of other types can be provided, for example mechanical retaining means.
The movingcarousel 131 and the step-varyingcarousel 132 are positioned in such a manner that, when therotating body 136 and the rotatingmember 138 are rotated, the handlingelements 137 and thegripping elements 139 define respective circular trajectories that are substantially tangential at a point W near which the containers C are transferred from the movingcarousel 131 to the step-varyingcarousel 132.Figures 12 to 17 show the movingcarousel 131, the step-varyingcarousel 132 and theconveyor belt 134 in subsequent steps of an operating cycle.
With reference toFigure 12, there is shown a step of the operating cycle in which, whilst agripping element 139a runs along an angular portion α1 measured from point W, a container C is exchanged between a movingcarousel 131 and the step-varyingcarousel 132.
With reference toFigure 13, there is shown a subsequent step of the operating cycle in which, whilst thegripping element 139a runs along an angular portion α2, the step-varyingcarousel 132 rotates at a maximum rotation speed. With reference toFigure 14, there is shown a subsequent step of the operating cycle in which, whilst thegripping element 139a runs along an angular portion α3, the step-varyingcarousel 132 decelerates to step from the maximum rotation speed to a minimum rotation speed.
With reference toFigure 15, there is shown a subsequent step of the operating cycle in which, whilst thegripping element 139a runs along an angular portion α4, the step-varyingcarousel 132 rotates at a constant speed corresponding to the minimum rotation speed until it reaches a further point Z, near which the container C is given to a retainingelement 135 of theconveyor belt 134.
With reference toFigure 16, there is shown a subsequent step of the operating cycle in which, whilst thegripping element 139a runs along an angular portion α5, the step-varyingcarousel 132 rotates at a constant speed corresponding to the minimum rotation speed.
With reference toFigure 17, there is shown a subsequent step of the operating cycle in which, whilst thegripping element 139a runs along an angular portion α6, the step-varyingcarousel 132 accelerates to pass from the minimum rotation speed to the maximum rotation speed. In particular, when a furthergripping element 139b, arranged downstream of thegripping element 139a with respect to the rotation direction of the step-varyingcarousel 132, is at point W the step-varyingcarousel 132 has reached maximum rotation speed.
The apparatus 1 further comprises a cooling and sanitisingcarousel 140.
The cooling and sanitisingcarousel 140 cools the containers C, bestowing greater mechanical resistance, in such a manner that the containers C are not deformed in the course of the subsequent operations. This is particularly useful in the case of containers provided with very thick walls, which, at the outlet from the formingcarousel 120, may comprise internal zones formed of plastics having a high temperature and, consequently, being easily deformable.
The cooling and sanitisingcarousel 140 is further provided with nozzles that dispense a sanitising fluid, for example an inert or liquid gas to perform washing of the containers C. The aforesaid washing in particular enables possible odours of plastics to be reduced or even eliminated. In particular, the cooling and sanitisingcarousel 140 can be received inside a casing that communicates with the outside only through openings of limited extent, arranged to enable the passage of the containers C. The zone enclosed by the aforesaid casing may be maintained in slight overpressure - for example with sanitised air - with respect to the external environment.
Instead of the cooling and sanitisingcarousel 140 two distinct carousels may be provided, one for cooling and one for sanitising, positioned in succession.
Theapparatus 101 further comprises a fillingcarousel 110 on which filling means is provided that fills the containers C with a product, this product being able to comprise a liquid material, a material made of powder or granules, a material made of paste and the like. The aforesaid product can be, for example, a food product or a cosmetic product. Theapparatus 101 is provided with a group of first transfer carousels 141 - or possibly a single first transfer carousel - by means of which the containers C are removed from the cooling and sanitisingcarousel 140 and are transferred to the fillingcarousel 110.
Theapparatus 101 further comprises a cappingcarousel 112 provided with capping means arranged for applying caps to the containers C filled with the product.
Theapparatus 101 is provided with asecond transfer carousel 142 arranged for removing the containers C from the fillingcarousel 110 and delivering the containers C to thecapping carousel 112.
Theapparatus 101 further comprises alabelling carousel 113 provided with applicating means arranged for applying labels to the containers C filled with the product.
Theapparatus 101 is provided with athird transfer carousel 143 arranged for removing the containers C from the fillingcarousel 110 and delivering the containers C to thecapping carousel 112.
With reference toFigures 18 and19 there is shown anapparatus 201 comprising a plasticising device, for example anextruder 202, arranged for dispensing plastics in a pasty state. With theextruder 202 cutting means is associated, which is not shown, that divides the plastics into doses. Theapparatus 201 further comprises a supplyingcarousel 250 that removes the doses and delivers the doses to a compression-moulding carousel 203. The compression-moulding carousel 203 supports a plurality of compression-moulding moulds each of which is provided with a female half mould provided with a cavity intended to receive a dose and with a male half mould arranged for being received inside the aforesaid cavity. The male half mould and the female half mould cooperate to shape the dose in such a manner as to obtain preforms P.
Theapparatus 201 further comprises a thermal conditioning device arranged for thermally conditioning the preforms P, for example to prepare the preforms P for a subsequent blowing step P.
The thermal conditioning device may comprise athermal conditioning carousel 208 and/or one or more thermal conditioning tunnels.
Theapparatus 201 further comprises a movingcarousel 251 that removes the preforms P from the compression-moulding carousel 203 and transfers the preforms to thethermal conditioning carousel 208.
The apparatus 1 further comprises a blow-moulding carousel 207 arranged for blowing thepreforms 6 to obtain containers. The blow-moulding carousel 207 comprises a plurality of blow-moulding moulds.
Downstream of the blow-moulding carousel 207 a filling carousel arranged for filling the containers with a product, and a capping carousel for capping the containers filled and a labelling carousel arranged for labelling the filled containers can be provided.
Between thethermal conditioning carousel 208 and the blow-moulding carousel 207 accumulatingmeans 252 is provided arranged for receiving the preforms P produced by the compression-moulding carousel 203.
In one embodiment, theapparatus 201 does not comprise thethermal conditioning carousel 208. In this case, the accumulating means 252 is interposed between the compression-moulding carousel 203 and the blow-moulding carousel 207.
The accumulating means 252 comprises achannel 253 inside which the preforms P are supplied one after the other to form arow 254. The accumulating means 252 further comprises moving means that moves the preforms along thechannel 253. The accumulating means 252 may comprise devices that prevent the preforms P from knocking against one another - or devices that soften blows - in such a manner that the preforms P are not damaged during conveying along thechannel 253.
Theapparatus 201 comprises afirst transfer carousel 255 arranged for removing the preforms P from thethermal conditioning carousel 208 and transferring the preforms P to thechannel 253 and asecond transfer carousel 256 arranged for removing the preforms P from thechannel 253 and transferring the preforms P to the blow-moulding machine 207.
Theapparatus 201 further comprises sensor means 257 arranged for detecting the quantity of preforms P present inside the accumulatingmeans 252.
The sensor means 257 comprises a plurality of sensors arranged in sequence along a direction F along which the preforms P advance along thechannel 253.
In particular, the sensor means 257 comprises afirst sensor 258, asecond sensor 259 and athird sensor 260, thefirst sensor 258 being nearer the blow-moulding carousel 207, thethird sensor 260 being further away from the blow-moulding carousel 207 and thesecond sensor 259 being interposed between thefirst sensor 258 and thethird sensor 260.
Thefirst sensor 258 detects whether the number of preforms P inside the accumulating means 252 is less than a minimum value, thesecond sensor 259 provides an indication of the average number of preforms P inside the accumulating means 252 and thethird sensor 260 detects whether the number of preforms P inside the accumulating means 252 is greater than a maximum value.
In an embodiment that is not shown, instead of the third sensor 260 a plurality of third sensors can be provided interposed between thefirst sensor 258 and thesecond sensor 259.
The following is a possible operating mode.
If thefirst sensor 258 detects that the number of preforms P inside the accumulating means 252 is less than the aforesaid minimum value - which corresponds to a situation in which the preforms P inside thechannel 253 have finished or are finishing - a command and control unit of theapparatus 201, connected to the sensor means 257, stops the blow-moulding carousel 207.
If thethird sensor 260 detects that the number of preforms P inside thechannel 253 is greater than the aforesaid maximum value, the command and control unit stops thethermal conditioning carousel 208 and the compression-moulding carousel 203.
During normal operation, the command and control unit regulates the speed of the blow-moulding carousel 207 in such a manner that the number of preforms P located inside the accumulating means 252 is comprised between the aforesaid minimum value and the aforesaid maximum value. According to operating mode, if thesecond sensor 259 does not detect the preforms P the command and control unit decreases the speed of the blow-moulding carousel 207, whereas if thesecond sensor 259 detects the preforms P the command and control unit increases the speed of the blow-moulding carousel 9.
With reference toFigures 20 to 22 a version of theapparatus 201 is shown comprising further accumulatingmeans 262, provided between the compression-moulding carousel 203 and thethermal conditioning carousel 208. The further accumulatingmeans 262 comprises afurther channel 263 inside which the preforms P are supplied one after the other to form afurther row 264.
Theapparatus 201 further comprises further sensor means 267 arranged for detecting the quantity of preforms P found inside the further accumulatingmeans 262.
The further sensor means 267 comprises a furtherfirst sensor 268, a furthersecond sensor 269 and a furtherthird sensor 270, the furtherfirst sensor 268 being nearer thethermal conditioning carousel 208, the furtherthird sensor 270 being further away from thethermal conditioning carousel 208 and the furthersecond sensor 269 being interposed between the furtherfirst sensor 268 and the furtherthird sensor 270.
The command and control unit interacts with the further sensor means 267 to manage the quantity of preforms in the further accumulatingmeans 262, with the methods disclosed with reference toFigures 18 and19.
Similarly, accumulating means cooperating with respective sensor means can also be provided between the blow-moulding carousel 207 and the filling carousel and/or between the filling carousel and the capping carousel and/or between the capping carousel and the labelling carousel.
In these cases, the accumulating means is conformed so as to receive containers, rather than preforms.
The accumulating means and the sensor means enable theapparatus 201 to operate with great flexibility.
Each of the components of the production line (carousels or devices of another type, for example tunnel conveyors), in fact, can be provided with dedicated driving means. Owing to the accumulating means and to the sensor means, the speed of each component can be varied to adapt to the speed of the component arranged upstream. Further, owing to the accumulating means and to the sensor means, a component can be maintained in operation, for a certain time, even if the component arranged upstream or downstream has been stopped. With reference toFigure 23, there is shown anapparatus 301 to produce preforms that are subsequently expanded to obtain containers intended for being filled with a product.
Theapparatus 301 is provided with a plasticising device, for example anextruder 302, suitable for dispensing plastics in a pasty state. With theextruder 302 there can be associated cutting means, which are not shown, that divide the plastics into doses.
Theapparatus 301 is provided with a compression-moulding machine, in particular a compression-moulding carousel 303, positioned in afirst operating zone 309. The compression-moulding carousel 303 is provided with a plurality of compression-moulding moulds - for example positioned at constant angular intervals on a peripheral zone of the compression-moulding carousel 303 - that compression-mould the doses to obtain preforms Z.
Each compression-moulding mould comprises a female half mould and a male half mould, that are movable towards and away from one another, the female half mould being provided with a cavity arranged for receiving a dose and the male half mould being provided with a punch arranged for penetrating inside the cavity to shape the dose.
Theapparatus 301 further comprises afirst transfer carousel 304, interposed between theextruder 302 and the compression-moulding carousel 303. Thefirst transfer carousel 304 removes the doses from theextruder 302 and inserts the doses into the compression-moulding moulds.
Thefirst transfer carousel 304, further removes the preforms Z obtained from the compression-moulding moulds and delivers the preforms Z to asecond transfer carousel 305.
Theapparatus 301 further comprises a blow-moulding machine, in particular a blow-moulding carousel 306, positioned in asecond operating zone 310. The blow-moulding carousel 306 is provided with a plurality of blow-moulding moulds 307 - for example positioned at constant angular intervals on a peripheral zone of the blow-moulding carousel 306 - that expand the preforms Z to obtain containers.
There is provided athermal conditioning station 308 interposed between the compression-moulding carousel 303 and the blow-moulding carousel 306 and configured for thermally conditioning the preforms Z so as to prepare the preforms Z for blowing. Thethermal conditioning station 308 is positioned in athird operating zone 311 interposed between thefirst operating zone 309 and thesecond operating zone 310.
Thethermal conditioning station 308 comprises a thermal conditioning tunnel. Aconveyor 318 is provided that advances the preforms Z along the tunnel of the thermal conditioning station. Theconveyor 318 moves along a trajectory, for example of the closed-loop type, in an advancing direction V. In an alternative embodiment, the conditioning station may comprise one or more thermal conditioning carousels and/or one or more thermal conditioning tunnels.
Upstream of thethermal conditioning station 308, in a loading zone C, atransferring wheel 315 is provided that rotates in an opposite direction to the advancing direction V of theconveyor 318. Upstream of the transferring wheel 315 athird transfer carousel 314 is provided. Thethird transfer carousel 314 receives the preforms Z that were obtained in the compression-moulding carousel 303 to give the preforms Z to thetransferring wheel 315 that, in turn, supplies the preforms Z to theconditioning station 308, so that the preforms Z can be thermally conditioned.
Theapparatus 301 comprises moving means 312 for moving the preforms Z to anintermediate zone 321 between the compression-moulding carousel 303 and thethermal conditioning station 308.
Owing to the moving means 312, it is possible to advance the preforms Z between the compression-moulding step and the conditioning step, along advance paths that can be selected in function of the type or geometry of the preform, i.e. in function of the time required by this type or geometry of preform to be subjected appropriately to the cooling step. In other words, it is not necessarily necessary to vary the operating speed of the compression-moulding carousel 303 and/or of the blow-moulding carousel 306 to adapt the latter to the speed at which the preforms Z are cooled, as theintermediate zone 321 acts as a temporary accumulation zone in which the preforms Z remain for a time of varying length, depending on the chosen advance path.
It is thus possible to maintain a high number of containers produced per unit of time, regardless of the type and/or geometry of preforms that are processed.
The moving means, in the embodiment shown inFigure 23 and, in greater detail, inFigures 24 to 26, comprises a movingcarousel 312 that is rotatable around a first rotation axis R1 in a first rotation direction R1. The movingcarousel 312 is placed downstream of thesecond transfer carousel 305, and upstream of thethird transfer carousel 314. Thesecond transfer carousel 305 and thethird transfer carousel 314 each rotate around a respective rotation axis parallel to the first rotation axis A1 and in a rotation direction opposite the first rotation direction R1.
The movingcarousel 312 is provided peripherally with a plurality of supportingcarousels 316, that can be distributed angularly in a uniform manner. Each supportingcarousel 316 can rotate around a respective second rotation axis A2.
In the disclosed example the movingcarousel 312 is provided with twelve supportingcarousels 316. In another embodiment it is possible to provide a different number of supportingcarousels 316, depending on the required needs.
Each supportingcarousel 316 comprises a plurality ofseats 317, each of which is conformed to receiving a respective preform Z. In the example shown inFigures 24 to 26 each supportingcarousel 316 is provided with fourseats 317 angularly distributed in an equidistant manner from one another, but it is possible to provide a different number ofseats 317.
Each supportingcarousel 316 is mounted rotatably on the movingcarousel 312. Each supportingcarousel 316, by rotating with respect to the movingcarousel 312, enables each of theseats 317 thereof to interact with thesecond transfer carousel 305 and/or with thethird transfer carousel 314 respectively to receive and give a preform Z.
The supportingcarousels 316, as also the movingcarousel 312, and/or other rotatable components of the apparatus, can rotate continuously or by angular steps.
The movingcarousel 312, and then the supportingcarousels 316 thus configured, are able to retain the preforms Z for a considerable time, if this is necessary for given types or geometries of preform. In this manner it is not necessary to have to slow down operation and thus the productivity of the compression-moulding carousel 308 to enable the preforms Z to cool.
The movingcarousel 312 and the supportingcarousels 316 act as accumulating means for the preforms Z. In other words, it is possible to drive each supportingcarousel 316 so as to receive one or more preforms Z each in arespective seat 317 depending on whether a lesser or greater period of time is required for the cooling step. In this manner, the preforms Z are advanced by the supportingcarousels 316 along advance paths having a desired length and chosen selectively so as to vary the dwelling time on the movingcarousel 312.
Theapparatus 301 that is thus configured defines a production line having high productivity in relation to reduced overall dimensions. Each of the components of theapparatus 301 can be provided with dedicated driving means. Owing to the movingcarousel 312 which acts as an accumulating device, the speed of each component can, in a certain manner, can be made independent of the speed of the component arranged upstream. It is further possible to maintain a component in function, for a certain time, even if the component arranged upstream, or downstream, has been stopped.
The supportingcarousels 316 can be rotated with respect to the respective second rotation axes A2 such as to make thermal conditioning possible, in particular a cooling step, only in certain and defined angular positions, or it is possible to provide a cooling step that is active for all the time in which the supportingcarousels 316 rotate. This may be advantageous for improving the thermal uniformity of the preforms and, particularly on each of the parts thereof, for example if there are thicknesses of the preforms Z that are variable from one zone to another zone.
The supportingcarousels 316 can be driven, i.e. rotated continuously or be rotated by successive angular steps independently from one another.
The movingcarousel 312 can be provided with a cooling system which enables the preforms Z to be cooled appropriately that are supported by the movingcarousel 312. The cooling system may comprise a plurality of cooling devices, each of which is associated with a respective supportingcarousel 316. In an embodiment it is possible to provide a cooling device for each of theseats 317 of each supportingcarousel 316.
The cooling device may provide suitable chambers inside which the preforms Z are received, the chambers being able to be closed above and below. The cooling device can be configured to send a cooling fluid both to internal surfaces of the preforms and to external surfaces of the preform. In one embodiment, it is possible to provide closing devices that bound, on each supportingcarousel 316, sector zones, in each of which a respective preform is received. The closing devices may comprise dividing-wall elements distributed in an equidistant manner by the respective preforms.
It is possible to configure the cooling system so as to act in a different manner according to the position that the preforms Z adopt whilst they are dragged by the movingcarousel 312. Cooling can, for example, be by flows of air and/or gas that are introduced into the aforesaid cooling chambers. The flows of air and/or gas can be directed to the preform in a coaxial manner or according to directions chosen in order to localise cooling in determined zones. It is possible, for example, to act to cool the external and the internal surfaces of the preforms Z in a different manner, depending on the different temperature values that obtain in various zones of the preform. For example the cooling device can take into account the fact that the temperature of the external surfaces of the preforms Z, at the end of compression-moulding, is less than the temperature of the internal surfaces.
Below, some operating methods of the movingcarousel 312 and of the supportingcarousels 316 are disclosed in greater detail below to explain the operation thereof better.
InFigure 24 there is shown a first operating mode of the movingcarousel 312 and of the supportingcarousels 316. In the first operating mode each supportingcarousel 316 is not rotated with respect to the movingcarousel 312, but is dragged only by the latter, which in turn rotates around the first rotation axis A1. In other words, the supportingcarousels 316 do not rotate around the respective second rotation axes A2. In this manner, only oneside 317 of each supportingcarousel 316 is used, in particular theseat 317 positioned nearer the peripheral zone of the movingcarousel 312. Each preform Z is thus transferred from thesecond transfer carousel 305 to aseat 317 in a first position P1, and is conducted via rotation of the movingcarousel 312 to a second position P2, in which each preform is given to thethird transfer carousel 314. In this manner, each preform moves along a first path that corresponds to a substantially semicircular trajectory.
A very reduced dwelling time of the preforms Z on the moving carousel corresponds to this first path. This is useful when the geometry and/or the type of preforms Z are such as to permit very rapid cooling steps.
Figure 25 shows a second operating mode in which the dwelling time of the preforms on the movingcarousel 312 is increased with respect to the first operating mode that has just been described. Of each supportingcarousel 316 only two of the fouravailable seats 317 are used. In particular, twoseats 317 are used that are diametrically opposite one another.
For each supportingcarousel 316 that is located in the first position P1, a first preform Z1 is received in a first seat 17a arranged more peripherally with respect to the movingcarousel 312 and nearer thesecond transfer carousel 305. Once the first preform Z1 is received, the supportingcarousel 316, which in the meantime is rotatingly dragged by the movingcarousel 312, rotates around the own second rotation axis A2 by approximately 180°. In this manner, thefirst seat 317 containing the first preform Z1 that has just been received is moved to a position diametrically opposite the previously occupied position (with respect to the second rotation axis A2). In other words, the first preform Z1 is moved from a more peripheral position to a central zone of the movingcarousel 312. When the supportingcarousel 316 is conducted to the position P2, in the meantime a preform Z0 already previously received by the movingcarousel 312 with respect to the first preform Z1, and which is thus suitably cooled, is given to thethird transfer carousel 314.
In the meantime, the movingcarousel 312 continues to rotate and takes the supportingcarousel 316 under examination again to thesecond transfer carousel 305 in the first position P1, in such a manner that a second seat 17b, diametrically opposite thefirst seat 317 can receive a second preform. At this point, the supportingcarousel 316 is rotated around the own second rotation axis A2 by a further angle equal to approximately 180° in such a way as to return thefirst seat 317 to a more peripheral position on the movingcarousel 312. In this manner, thefirst seat 317 can interact, in the second position P2, with thethird transfer carousel 314, giving to the latter the first preform. A this point, the movingcarousel 312 continues to rotate and thefirst seat 317, which is now free, is again moved to thesecond transfer carousel 305 to receive the third preform. Subsequently, the supportingcarousel 316 is rotated by a still further angle of 180° so as to give also the second preform to thethird transfer carousel 314 in the second position P2 and so on. What has just been described applies to each of the supportingcarousels 316. In substance, in this operating mode, each preform is retained on the movingcarousel 312 in such a way as to define a second path corresponding substantially to one and a half revolutions of the movingcarousel 312. In such a manner a dwelling time is used that is three times the dwelling time associated with the first operating mode disclosed above, i.e. if thesecond transfer carousel 305 and thethird transfer carousel 314 are located in positions that are diametrically opposed to one another with respect to the movingcarousel 312.
Figure 26 shows a third operating mode that enables all fourseats 317 of each supportingcarousel 316 to be exploited. In this operating mode, the dwelling time of the preforms Z on the movingcarousel 312 is at maximum with respect to the previously disclosed cases. Each supportingcarousel 316, whilst it is conveyed by the movingcarousel 312 from the first position P1 to the second position P2, rotates around the respective second axis A2 by a quarter revolution so as to give a now cooled preform Z to thethird transfer carousel 314. The seat that is freed receives a further preform Z from thesecond transfer carousel 305 and so on. In this case - in which there are fourseats 317 for each supporting carousel 316 - each supportingcarousel 316 rotates around the second rotation axis A2 by successive angles equal to approximately 90° in such a manner that eachseat 317, in a sequential manner receives a preform Z and subsequently gives the preform Z after a set number of revolutions of the movingcarousel 312. In this case each preform Z moves along a path having a length corresponding to three and a half revolutions of the movingcarousel 312.
The dwelling time in this operating mode is seven times that of the first operating mode disclosed above.
Obviously, and in an operating mode that is similar to what has been seen so far, one operating mode is provided that is not shown in which three of the fourseats 317 of each supportingcarousel 316 are used.
A similaroperation moving carousel 312 to what is disclosed above is provided if there is a different number of supportingcarousels 317 and/or a different number ofseats 317 on each supportingcarousel 316.
In the various embodiments of theapparatus 301 disclosed above, it is possible to provide on the movingcarousel 312 heating means that acts on the preforms Z, after the cooling step, so as to perform a slight heating step on the latter. The heating means can act selectively on certain critical parts of each preform Z that need to be prepared for the subsequent and more thorough step of thermal conditioning that occurs in thethermal conditioning station 308. In this manner it is possible to eliminate or substantially reduce possible thermal imbalances in the preforms Z.
The heating means can act at set angular positions of each supportingcarousel 316 and/or of the movingcarousel 312.
The preforms Z, after remaining on the movingcarousel 312 for the time necessary for cooling, are given to thethird transfer carousel 314, which in turn delivers the preforms Z to thetransferring wheel 315. Thetransferring wheel 315, lastly, transfers the preforms Z to theconditioning station 308 where the preforms Z can receive suitable thermal treatment that has the purpose of preparing the preforms Z for successive blow-moulding on the blow-moulding carousel 306.
Downstream of theconditioning station 308 there is provided afourth transfer carousel 319, suitable for transferring the preforms Z exiting theconditioning station 308 to the blow-moulding carousel 306. Downstream of the conditioning station 308 afifth transfer carousel 320 is provided that is used to remove from the blow-moulding carousel 306 the containers obtained from the preforms Z and send the containers to possible operating stations located further downstream. Such operating stations may comprise, for example, a filling station for filling the containers with a product, for example a liquid material, a powder or granule material, a paste material and the like. The aforesaid product can be, for example, a food product or a cosmetic product. It is possible also to provide a closing or capping station to close the containers that are possibly filled and/or a labelling station for the containers.
With reference toFigure 23, theapparatus 301 comprises astorage station 322, positioned in a storing zone (332) and provided, for example, with ahopper 323 suitable for containing preforms.
Abypass device 328 is provided that enables the preforms to be directed to thestorage station 322. In this manner it is possible to conserve the compression-moulded preforms that do not have to be sent immediately to the blow-moulding carousel 306 but can be processed subsequently. Thestorage station 322 can also receive preforms that have been produced elsewhere, for example injection-moulded preforms.
Thebypass device 328 comprises abypass conveyor 324 that connects the movingcarousel 312 to thehopper 323. Thebypass conveyor 324 can be, for example, of the belt or chain type.
Thebypass device 328 comprises a removingwheel 331 suitable for removing the preforms Z from the movingcarousel 312 to position the preforms Z on thebypass conveyor 324.
Owing to the embodiment of theapparatus 301 inFigure 23, it is possible to produce preforms Z and conserve the preforms Z for any period of time that is desired, postponing the blow-moulding of the preforms Z to a subsequent moment. In this operating mode, it may be necessary to perform more thorough cooling of the preforms Z on the movingcarousel 312, to prevent the preforms Z possibly being damaged in the subsequent conveying and storage steps. For this purpose, it is possible to increase the dwelling time of the preforms Z on the movingcarrousel 312, operating the latter, for example in the second operating mode, disclosed with reference toFigure 25, or in the third operating mode, disclosed with reference toFigure 26. The operating mode of the movingcarousel 312 can be varied by acting on a control unit and setting a change to the operating programme.
The preforms Z are cooled on the movingcarousel 312 so as to have a temperature below a set value in order to avoid crystallisation thereof. In one embodiment, on thesecond transfer carousel 305 there can be provided air and/or gas cooling means configured for thermally conditioning the preforms Z in a preliminary manner, i.e. in such a manner as to anticipate the thermal conditioning that subsequently takes place on the movingcarousel 312. Also in this case, the cooling means can be configured for acting in a selective manner on given zones of the preforms Z, and/or at determined angular positions of thesecond transfer carousel 305.
Theapparatus 301 can be provided with a discarding device that discards the preforms having certain defects that are detectable with suitable vision systems. The discarding device can be provided on the removingwheel 331 and/or on thethird transfer carousel 314.
A supplyingsystem 326 is further provided that is suitable for removing the preforms stored in thestorage station 322 to insert preforms into the production line defined byapparatus 301.
The supplyingsystem 326 comprises a supplyingconveyor 325 suitable for conveying the preforms from thestorage station 322 to theconditioning station 308.
Downstream of the supplyingconveyor 325 there is provided afurther transferring wheel 327, suitable for transferring the preforms coming from thestorage station 322 to theconditioning station 308. In particular, thefurther transferring wheel 327 transfers the preforms from the supplyingconveyor 325 to theconveyor 318 of theconditioning station 308 in a further loading zone D, opposite the loading zone C, with respect to theconveyor 318. Thefurther transferring wheel 327 is connected so as to be upstream of thetransferring wheel 315 with respect to the advancing direction V of theconveyor 318. In this manner, the preforms that arrive from thestorage station 322 and that may thus require a more thorough thermal conditioning step with respect to the preforms coming from the compression-moulding carousel 303, can travel, via theconveyor 318, along a trajectory of greater length inside the conditioning tunnel.
The supplyingsystem 326 and/or the supplyingconveyor 325 is configured for suitably orientating the preforms removed from thestorage station 322.
Figure 27 shows anotherapparatus embodiment 301 that differs from the embodiment disclosed with reference toFigure 23 inasmuch as thebypass device 328 is not provided. In this case, theapparatus 301 can process preforms that have just been obtained in the compression-moulding carousel 303 or preforms that are removed from thestorage station 322 and were previously obtained. The preforms coming from thestorage station 322 can be of a different nature, for example they can be produced by injection moulding in a production plant that is distinct from theapparatus 301.
With reference toFigure 28, there is shown a still further embodiment of theapparatus 301 that is different from the preceding embodiments inasmuch as neither thebypass device 328 nor thestorage station 322 and thus the supplyingsystem 326 are provided.
In this embodiment, theapparatus 301 comprises aconditioning station 329 similar to that disclosed in theapparatus embodiments 301 shown inFigures 23 and27 but provided with a conditioning tunnel of reduced length. Afurther conveyor 330 is provided that advances in a further advancing direction V'. In this case, thetransferring wheel 315 is positioned at an end of the tunnel that is nearer thefourth transfer carousel 319.
The preforms that are dropped from thetransferring wheel 315 to thefurther conveyor 330 run along the tunnel first in one direction, away from thefourth transfer carousel 319, and then in the opposite direction, towards thefourth transfer carousel 319. Owing to this configuration, it is possible to thermally conditioning the preforms in an effective manner and simultaneously the overall dimensions associated with theconditioning station 308 are reduced significantly. Variations and/or additions to what has been disclosed and illustrated in the enclosed drawings are possible.
In particular, any moving means can be used that defines advance paths of variable lengths so as to be able to obtain variable dwelling times of the preforms between the compression-moulding and the thermal conditioning zones of the preforms.

Claims

Apparatus comprising a compression-moulding machine (303), suitable for compression-moulding plastics to obtain preforms (Z, Z0, Z1), a blow-moulding machine (306), suitable for blowing said preforms (Z, Z0, Z1) to obtain containers, a thermal conditioning station (8, 29) for said preforms (Z, Z0, Z1), interposed between said compression-moulding machine (303) and said blow-moulding machine(306), moving means (312) for moving said preforms (Z, Z0, Z1) to an intermediate zone (321) between said compression-moulding machine (303) and said thermal conditioning station (8, 29),characterised in that said moving means (312) is configured so as to advance said preforms (Z, Z0, Z1) along advance paths of variable length to vary the dwelling time of said preforms (Z, Z0, Z1) in said intermediate zone (321).
Apparatus according to claim 1, wherein said moving means comprises moving carousel means (312).
Apparatus according to claim 2, wherein said moving means comprises supporting carousel means (316) rotatably supported by said moving carousel means (312); wherein said supporting carousel means optionally comprises a plurality of supporting carousels (316) peripherally distributed on said moving carousel means (312); wherein on said supporting carousel means (316) there are optionally obtained seats (17, 17a, 17b) suitable for receiving respective preforms (Z, Z0, Z1).
Apparatus according to any one of claims 1 to 3, further comprising thermal conditioning means for thermally treating said preforms (Z, Z0, Z1) when they are supported by said moving means (312).
Apparatus according to claim 4, wherein said thermal conditioning means comprises:
cooling means for cooling said preforms (Z, Z0, Z1); and/or
closing-wall-means defining chambers, each of which suitable for receiving a respective preform (Z, Z0, Z1); and/or
heating means suitable for pre-heating said preforms (Z, Z0, Z1) before said preforms (Z, Z0, Z1) are sent to said conditioning station (308).
Apparatus according to any one of claims 1 to 5, further comprising a storage station (322) for said preforms (Z, Z0, Z1) and/or for further preforms produced by injection moulding.
Apparatus according to claim 6, further comprising:
a supplying device (326) configured for removing from said storage station (322) preforms to be sent to said conditioning station (308); and/or
a supplying conveyor (325) for conveying preforms from said storage station (322) to said conditioning station (308); and/or
a bypass device (328) configured for removing preforms (Z, Z0, Z1) from said moving means (312) and for sending said preforms (Z, Z0, Z1) to said storage station (322), wherein said bypass device (328) optionally comprises a removing wheel (331) configured for interacting with said moving means (312) and/or wherein said bypass device (328) optionally comprises a bypass conveyor (324) suitable for conveying said preforms (Z, Z0, Z1) from said moving means (312) to said storage station (322).
Apparatus according to any one of claims 1 to 7, further comprising discarding means suitable for discarding the preforms having defects.
Apparatus according to claim 8, further comprising a storage station (322) for said preforms (Z, Z0, Z1) and/or for further preforms produced by injection moulding; the apparatus further comprising a bypass device (328) configured for removing preforms (Z, Z0, Z1) from said moving means (312) and for sending said preforms (Z, Z0, Z1) to said storage station (322), wherein said bypass device (328) comprises a removing wheel (331) configured for interacting with said moving means (312), wherein said discarding means is provided on said removing wheel (331).
Apparatus according to claim 8, further comprising transfer carousel means (314) for transferring said preforms (Z, Z0, Z1) from said moving means (312) to said thermal conditioning station (308), wherein said discarding means is provided on said transfer carousel means (314).
Apparatus according to any one of claims 1 to 10, further comprising further transfer carousel means (305) for transferring said preforms (Z, Z0, Z1) from said compression-moulding machine (303) to said moving means (312), wherein said further transfer carousel means (305) optionally comprises further cooling means for cooling said preforms (Z, Z0, Z1).
Apparatus according to any one of claims 1 to 11, further comprising:
transfer carousel means (314) for transferring said preforms (Z, Z0, Z1) from said moving means (312) to said thermal conditioning station (308); and/or
a filling station suitable for filling said containers with a product; and/or
a closing station suitable for closing said containers; and/or
a labelling station for labelling said containers.
Method comprising compression-moulding plastics to obtain preforms (Z, Z0, Z1) in a first operating zone (309), blow-moulding said preforms (Z, Z0, Z1) to obtain containers in a second operating zone (310), thermally conditioning said preforms (Z, Z0, Z1) in a third operating zone (311) interposed between said first zone (309) and said second zone (310), moving said preforms (Z, Z0, Z1) to an intermediate zone (321) interposed between said first operating zone (309) to said second operating zone (310),characterised in that said moving comprises advancing said preforms (Z, Z0, Z1) along advance paths of variable length to vary the dwelling time of said preforms (Z, Z0, Z1) in said intermediate zone (321).
Method according to claim 13, wherein said advance paths comprise at least part of substantially circular trajectories, and/or
wherein said one or more advance paths comprise trajectories closed in a loop, and/or
wherein during said moving cooling said preforms (Z, Z0, Z1) is provided, and/or
wherein after said moving storing said preforms (Z, Z0, Z1) in a storing zone (332) is provided, the method optionally comprising removing from said storing zone (332) preforms (Z, Z0, Z1) to be sent to said third operating zone (311).
Method according to claim 13 or 14, further comprising filling said containers with a product, and/or closing said containers, and/or labelling said containers.